This invention relates to a forced air heat transfer system of the type that circulates air throughout a building via ductwork that conducts the air around a heat exchanger to heat or cool the air. More particularly, the invention relates to a damper assembly for introducing fresh, outside air to the heat transfer system.
Recent research indicates that conventional forced air heating or air conditioning systems adversely affect the ion balance within the enclosure heated or cooled. Preferably, the negative and positive ions within the enclosure should be balanced, but the ductwork by means of which the heating or cooling air is distributed, as well as the incorporation of electronic air cleaning devices, results in a deficiency of negative ions and an overabundance of positive ions, or a deficiency in both kinds of ions. The use of synthetic, plastics materials within the enclosure also contributes to the ion imbalance or deficiency. Such an ion imbalance or deficiency has many disadvantageous effects, particularly on the health of the occupants of the enclosure. It has been demonstrated that the ion imbalance can be overcome, to a large extent, by the addition of fresh air to the heat exchanger of both heating and air conditioning systems. For further details on such research reference is made to Volumes I and II of Proceedings of International Conference on Ionization of the Air, Oct. 16 - 17, 1961, published by Franklin Institute, Philadelphia, Pennsylvania.
Apparatus for introducing fresh air to a heating system for a building are disclosed in U.S. Pat. Nos. 2,962,218, 2,009,643 and 3,204,870. Such apparatus includes a fresh air conduit in communication with outside fresh air and a damper or baffle plate swingably mounted in the conduit for adjusting the flow of air through the conduit. Although the conduits in which damper assemblies of this type normally are substantially horizontal, it is sometimes desirable due to limited space, for example, to mount such conduit vertically. To minimize the inventory and to minimize manufacturing and assembly costs, it is desirable to provide a damper assembly which can be mounted in either a vertical or horizontal conduit. Accordingly, it is an object of the present invention to provide a damper assembly of the type described including an air intake conduit which can be mounted in any selected one of a plurality of vertically or horizontally disposed positions.
A damper assembly constructed according to the present invention incorporates a counterbalance which is mounted on a damper or baffle plate that is movably mounted internally of a conduit for conducting fresh air to the heating system. The counterbalance is adjustably mounted on the baffle plate for movement to selected positions depending on the orientation of the conduit. The apparatus includes another adjustably mounted counterbalance connected to the damper or baffle plate but disposed exteriorly of the conduit for calibrating the counterbalancing system after installation of the damper assembly on the furnace. Accordingly, it is another object of the present invention to provide apparatus of the type described including a counterbalance mounted on the damper internally of the conduit and another counterbalance adjustably mounted exteriorly of the conduit to permit calibration of the counterbalancing system after installation.
Still another object of the present invention is to provide apparatus of the type described including a counterbalance which is adjustably mounted on the damper so as always to urge the damper to a conduit closing position regardless of the horizontal or vertical orientation of the fresh air conduit.
A still further object of the present invention is to provide apparatus of the type described including gauging means removably attached to the outside of the conduit for indicating the condition of filters or the like with which the furnace customarily is equipped.
Other objects and advantages of the present invention will become apparent to those of ordinary skill in the art as the description thereof proceeds.